Apple selling out of first-day delivery pre-orders for some new iPad models

Suggesting strong demand for the new iPad at launch, shipping estimates for the white 4G LTE model from AT&T have shipped to March 19 at Apple's online store.

Both the 16-gigabyte and 64-gigabyte models are now advertised to ship by March 19, while the 32-gigabyte model is still shown to deliver on March 16.

There are not yet any delays for the Wi-Fi-only models, or any of the Verizon models. In addition, all of the black third-generation iPad models compatible with AT&T remain available for delivery on March 16.

Next Friday's iPad launch marks the most ambitious debut yet for a new version of Apple's touchscreen tablet. It will launch on day one in a total of 10 countries: the U.S., Canada, the U.K., France, Germany, Switzerland, Japan, Hong Kong, Singapore and Australia.

Demand for the iPad is expected to continue to grow, bolstered by the Retina Display on the latest model, as well as a lower $399 entry price for the 16-gigabyte Wi-Fi-only iPad 2. The 3G-capable 16-gigabyte iPad 2 is also available for $529.

One estimate made before the third-generation iPad was announced projected that Apple will sell 55 million units in 2012. And analysts on Wall Street are in agreement that Apple will continue to dominate the tablet market, where it has maintained above 70 percent share despite a growing number of less expensive competitors, like Amazon's $199 Kindle Fire.